createMySQL - db-mysql documentation

function createMySQL



createMySQL(options?: MySQLOptions): MySQLConnector

Creates a MySQL connector with connection pooling.

Uses mysql2 with promise API for MySQL databases. The connection pool manages multiple connections for concurrent operations. Each adapter acquisition gets a connection from the pool; releasing returns it.

Examples

Connect with connection string

import { DB } from "@anabranch/db";
import { createMySQL } from "@anabranch/db-mysql";

const users = await DB.withConnection(
  createMySQL({ connectionString: "mysql://user:pass@localhost:3306/mydb" }),
  (db) => db.query("SELECT * FROM users")
).run();

Concurrent processing with retry on failure

import { DB } from "@anabranch/db";
import { createMySQL } from "@anabranch/db-mysql";

const { successes, errors } = await DB.withConnection(createMySQL(), (db) =>
  db.stream("SELECT * FROM users")
    .withConcurrency(5)
    .map(async (user) => {
      const profile = await fetchProfile(user.id);
      return enrichUser(user, profile);
    })
    .retry({ attempts: 3, delay: 100 })
    .partition()
).run();

Transactions with error handling

import { DB, ConstraintViolation } from "@anabranch/db";
import { createMySQL } from "@anabranch/db-mysql";

const result = await DB.withConnection(createMySQL(), (db) =>
  db.withTransaction(async (tx) => {
    await tx.execute("INSERT INTO orders (user_id, total) VALUES (?, ?)", [userId, total]);
    await tx.execute("UPDATE users SET order_count = order_count + 1 WHERE id = ?", [userId]);
    return tx.query("SELECT LAST_INSERT_ID()");
  })
).recoverWhen(
  (e) => e instanceof ConstraintViolation,
  (e) => ({ id: 0, error: e.message })
).run();

Parameters

optional



options: MySQLOptions

Return Type

MySQLConnector